Lapper



March 2 1926.

W. M. HOU LDSWORTH LAPPER Filed April 5, 1923 \INVENTORL 1 I TTORNE Y.

Patented Mar. 2, 1926. UNITED STATES 1,575,267 PATENT OFFICE.

WALLACE M. HOULDSWORTH, OF ROYAL OAK, MICHIGAN.

Lanna.

Application filed April 5, 1923. Serial No. 639,971.

II '0 all whom it may concern:

Be it known that I, WALLACE M. HoUnnswon'rn, a citizen of the United States, residing at Royal Oak, county of Oakland, State v of Michigan, have invented a certain new sion in .the

and useful Improvement in Lappers, and declare the following to be a full, clear, and exact description of the same, such as will enable others skilled in the art to which it pertains to make and use the-same, reference being had to the accompanying drawin which form a part of this specification.

y invention relates to an improved la ping machine. It is illustrated n a s eci c embodiment intended. for use with cyhnders or other tubular bodies.

An object is to provide an improved rotary lapper adapted to finish a cylinder or other s1milar' work to a true radius, and which will remove an out-of-round irregularity existing in such body and will not conform in its rotation to such an out-of round condition and accentuate it, and a meritorious characteristic of my improvement is the use of a lapping element so constructed as to engage the lapped surface at a plurality of circumferentially spaced ploints, thereby preventing a lapping stone om falling into an out-of-round depresa' pad surface.

A further 0 met is to provide a rotatable lapper having lapping stones held normally outwardsby uniform yielding pressure" to engage the work, which stones may be retracted radially to permit-withdrawal of the lapper from the work without interrupting the rotation of the work, and an important feature of this improved construction is the provision of mechanism so arranged that the rotation of the lapper may be utilized to retract the lapping stones to proved lapper.

permit withdrawal of the lapper from the piece upon which it is working.

In tlfe drawings,-

Figure 1 is a side elevation of my im- Fig. 2 1s a cross-sectional view taken on the line 22, Fig. 1.

Fig. 3 isa bottom plan of the lapper shown in Fig. 1.

Fig. 4 is a sectional view taken on the line.4-4, Fig. 2.

'Fig. 5 1s a sectional view taken on the ,line 5-5 of Fig. 2.

My improved lapper comprises a-sup rting body provided with a suitable sfiiink power-driven rotatable spindle to rotate therewith, which body is adapted to carry a plurality of removable lapping stones held yielding outwards to engage a piece of work, which stones are so constructed as to individually engage the work at a plurality of circumferentially spaced apart points through an arc of sufiicient extent to prevent any' stone from falling into an out-of-round depression in the lapped surface.

I provide a supporting body 10 cored out to provide a plurality of spaces 11, which body is carried by a suitable shank 12 secured to the body by a plate 13. This plate 13 is secured to the end of the shank by a screw 141: and to the body by a plurality of screws 15. The body 10 is provided with a plurality of spiral grooves 16, each of upward pressure as well as outward pressure on the several lapping stones and also exert a uniform pressure on each of the lapping stones. The springs here shown are flat spring members provided with radial extensions to engage each lappingstone. These springs are disposed in the cut-out, portions 11 of the body and may be held in place by means of suitable screws. The uppermost spring 18 is secured in "position by a sleeve. 22 which is interposed between the plate 18 and a shoulder formed on the shank. The

next lowermost spring is held in position by a screw 19engaging it to the body, as appears in Fig. 2. The lowermost sprin 18 is secured in position by a screw 20, w ich screw also secures a retaining plate 21 to the lower end of the body, a spacer tube 22 encirclin the screw between the retainer plate an the spring to hold the spring upwardly within the body.

The lapping stones will have a limited radial movement, as will appear from. the drawing, and are held in place by retaining plates at each end. Each lapping stone is beveled at the ends and the retaining plates are 'so shaped as. to engage these .beveled .ends. The retaining plate 21 which is secured to the lower end of the body by a screw 22 engages the lower end of the apping stones and an axially movable retaining plate 23 engages the upper extremities of the lapping stone's. This retaining plate-23 is held outwardly to .engage the lapping I stones by a spring 24, one end of whichengages the plate and the other end of which is received within a recess. 25 formed in a gripping member 26. This gripping memit is desired to remove the lapper, this may be done without interrupting the rotation of the lapping tool by gripping with the hand the gripping member 26 so a 's to arrest its rotation, which will permit the shank to overrun the gripping member and cause the gripping member to move'dowir wardly over the shank as the pins 27 travel downwardly through the groove 28 circumferentially the shank, This downward movement of the gripping member axially 30 the shank forces the retaining plate 23 radially the tool against the outward yi downwardly and due to the beveled construction of the ends of the lapping stones causes the lapping stones to move inwardlly ing pressure maintained thereon by the mate the lowermost extension thereo springs 18 and permitsthe withdrawal of:

the lapping tool from the work. The spiral groove 28 is provided at a point ap mma ocket 29, into which the pin 27- may iall w en it registers therewith. This will serve to secure the gripping member in the depressed positlon and retain the lapping.

stones in the retracted position.

What I claim is:

1. In a lapper,'in combination, a rotatable body having a plurality of seats for spiral lapping elements, a plurality of spiral lap ping elements individually removably re- 'ceivable within the provided sea-ts of the body, said elements extending lengthwise the body and circumferentially thereof but less than half way around the body, and releasable retaining means engaging the ends of said elements to secure them in their provided seats adapted to permit limited movement radially of the elements during operation. I Y

2. In a lapper, the combination with a rotatable body havinga su port for aspiral lapping element, a spira lapping element having beveled ends .dis osed within said -e ement' having beveled ends disposed with in said seat, end plates engaging the beveled ends of said lapping element to hold the same removably in place adapted to permit radial movement of the lapping element relative its seat, one of said end plates held against said lappin element under yielding pressure to yiel axially, spring members holding said lapping element yieldably outwardly radially a gr1 ping member normally rotatable with sai support engaging therewith and with the movable end plate to force the plate axially to actuate the apping element radially upon the arrest of rotation of the gripping member permitting the support to'overrun the same. a

4. In a lapper, a rotatable tool-holding body having beveled ends and a spiral seat 'for a lapping element, a lap ing element having beveled. ends positione within the spiral seat of the body, end plates carried by the body adapted to en a e the beveled ends thereof and the ends 0 t e lapping ele-.

ment to hold the element u on its seat adapted to permit movement 0 the, element radially upon its seat, one of said-end plates held yieldably in engagement with the lap--,

ping element.

5. In a lapper, a rotatable tool-holding body having a plurality of spiral seats 'for lapping elements, said body cored out interiorly, 's ring members dis osed-therein,

each mem r having a plura ity of leaves,

one engaging each lappling element to exert pressure thereon radia y.

6. In a lapper, av rotatable tool-holding body having a pluralit of spiral seats for lapping elements, said od cored out intoriorly, spring members isposed therein, each member having a plurality of leaves, one engaging each la ing element to exert pressure thereon radia -y, said lap ing elements having beveled ends,-beve ed end plates enga in the ends of said lapping ele ments to 01 them 11 on their provided seats, one of said end plates being stationary, the other end (plate held against-the lapping elements un er yieldable adjustable pressure. e p

In testimony whereof 'I sign this specification.

WAIJLACE nnbunnswon'rn. 

